An excavating machine consisting of steel knives to cut the earth, iron scoops, buckets and dippers to scoop it up, endless chains or cranes to lift them, actuated by steam, and operated by a single engineer, will excavate cubic yards of earth by the minute and at a cost of but a few dollars a day.

Dredging machines of a great variety have been constructed. Drags and scoops for elevating, and buckets, scrapers and shovels, and rotating knives to first loosen the earth, suction pumps and pipes, which will suck great quantities of the loosened earth through pipes to places to be filled—these and kindred devices are now constantly employed to dig and excavate, to deepen and widen rivers, to drain lands, to dig canals, to make harbours, to fill up the waste places and to make courses for water in desert lands.

Inventions for the excavating of clay, piling and burning it in a crude state for ballast for railways, are important, especially for those railways which traverse areas where clay is plentiful, and stones and gravel are lacking.

Sinking shafts through quicksands by artificially freezing the sand, so as to form a firm frozen wall immediately around the area where the shaft is to be sunk, is a recent new idea.

Modern countries especially are waking up to the necessity of good roads, not only as a necessary means of transportation, but as a pre-requisite to decent civilisation in all respects. And, therefore, great activity has been had in the last third of a century in invention of machines for finishing and repairing roads.

In the matter of sewer construction, regarded now so necessary in all civilised cities and thickly-settled communities as one of the means of proper sanitation, great improvements have been made in deep sewerage, in which the work is largely performed below the surface and with little obstruction to street traffic.

In connection with excavating and dredging machines, mention should be made of those great works in the construction of which they bore such important parts, as drainage and land reclamation, such as is seen in the modern extensions of land reclamation in Holland, in the Haarlem lake district in the North part of England, the swamps of Florida and the drainage of the London district; in modern tunnels such as the Hoosac in America and the three great ones through the Alps: the Mont Cenis, St. Gothard, and Arlberg, the work in which developed an entirely new system of engineering, by the application of newly-discovered explosives for blasting, new rock-drilling machinery, new air-compressing machines for driving the drill machines and ventilating the works, and new hydraulic and pumping machinery for sinking shafts and pumping out the water.

The great canals, especially the Suez, developed a new system of canal engineering. Thus by modern inventions of devices for digging and blasting, dredging and draining and attendant operations, some of the greatest works of man on earth have been produced, and evinced the exercise of his highest inventive genius.

If one wishes an ocular demonstration of the wonders wrought in the 19th century in the several domains of engineering, let him take a Pullman train across the continent from New York to San Francisco. The distance is 3,000 miles and the time is four days and four nights. The car in which the passenger finds himself is a marvel of woodwork and upholstery—a description of the machinery and processes for producing which belongs to other arts. The railroad tracks upon which the vehicle moves are in themselves the results of many inventions. There is the width of the track, and it was only after a long and expensive contest that countries and corporations settled upon a uniform gauge. The common gauge of the leading countries and roads is now 4 feet 8½ inches. A greater width is known as a broad gauge, a less width as a narrow gauge. Then as to the rail: first the wooden, then the iron and now the steel, and all of many shapes and weights. The T-rail invented by Birkensaw in 1820, having two flanges at the top to form a wide berth for the wheels of the rolling stock, the vertical portion gripped by chairs which are spiked to the ties, is the best known. Then the frogs, a V-shaped device by which the wheels are guided from one line of rails to another, when they form angles with each other; the car wheel made with a flange or flanges to fit the rail, and the railway gates, ingenious contrivances that guard railway crossings and are operated automatically by the passing trains, but more commonly by watchmen. The car may be lighted with electricity, and as the train dashes along at the rate of 30 to 80 miles an hour, it may be stopped in less than a minute by the touch of the engineer on an air brake. Is it midwinter and are mountains of snow encountered? They disappear before the railway snow-plough more quickly than they came. It passes over bridges, through tunnels, across viaducts, around the edges of mountain peaks, every mile revealing the wondrous work of man’s inventive genius for encompassing the earth with speed, safety and comfort. Over one-half million miles of these railway tracks are on the earth’s surface to-day!

Not only has the railway superseded horse power in the matter of transportation to a vast extent, but other modes of transportation are taking the place of that useful animal. The old-fashioned stage coach, and then the omnibus, were successively succeeded by the street car drawn by horses, and then about twenty years ago the horse began to be withdrawn from that work and the cable substituted.